With the Ospreys suffering a tighthead prop crisis with injuries to Adam Jones, Aaron Jarvis and Joe Rees, the region included Cai Griffiths – back on loan from London Irish for the rest of the season – and brought Moldovan front-rower Dmitri Arhip on for the final 10 minutes.

Ospreys scrum-half Kahn Fotuali’i carried on from his man-of-the-match performance for Samoa in their win over Wales as the home side opened up a 16-6 interval lead.

The lively No. 9 went closest after fellow Samoan George Stowers charged down a kick by Lloyd Williams.

A good, strong scrummage from the Ospreys earned them a penalty on 10 minutes which Matthew Morgan converted. It heralded a period of total home domination.

It did not help the Blues' cause that they lost No. 8 Robin Copeland with a hip injury.

The Ospreys continued on the front foot as they scored a try three minutes later. Lock James King went in at the corner after winning a lineout, with Fotuali’i and Joe Bearman involved in the build-up. Morgan kicked the extras.

More positive play from the home side saw the Blues penalised at a ruck but Morgan was unusually wide of the mark.

But Morgan made up for that with a penalty on 24 minutes after the Blues came in from the side at a maul.

That kick was cancelled out by a Ceri Sweeney penalty two minutes later.

More Ospreys domination at the scrum earned them a penalty in the Blues 22 which Morgan kicked to restore a 13-point lead.

But just before the break Sweeney converted his second penalty

It took the Ospreys 71 seconds of the second half to score their second try when full-back Richard Fussell went over after latching on to wing Ross Jones’ kick ahead.

The Blues did launch something of a comeback with two Rhys Patchell penalties – the second one after Sam Lewis was sin-binned for a professional foul.

But it was the Ospreys who scored next with Morgan putting over his fourth penalty.

The Blues found themselves with more territory in the final 15 minutes but could not make it count on the scoreboard.

A weaving run by Eli Walker saw Blues captain Josh Navidi sin-binned for slowing ball at a ruck before Allen went over in the final minute.

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